1. Field of the Invention
The present invention relates to an electric vehicle which travels by transmitting a driving force of a motor mounted at a front portion of a vehicle body through a reduction device and differential to front driven wheels.
2. Description of the Related Art
FIG. 9 shows a conventional electric vehicle. A power unit 01 mounted at a front portion of a vehicle body is integrally provided with a motor 02, a reduction device 03 and a differential 04, wherein front wheels 07, 07 are driven for traveling of the vehicle by supplying power of batteries 05 mounted at a central portion of the vehicle body through a control unit 06 to the motor 02.
The above conventional electric vehicle suffers from a problem in that it is difficult to enlarge a crushable zone which is crushed upon a collision of the vehicle to absorb a shock, because the motor 02 and the reduction device 03 are disposed at portions of the vehicle body in front of the differential 04. In addition, the motor 02 and the reduction device 03 which are heavy components are disposed at locations largely spaced forwards apart from the center of gravity of the vehicle, which is disadvantageous from the viewpoint of enhancing a in motional property of the vehicle.
Accordingly, it is an object of the present invention to provide an electric vehicle in which front wheels thereof are driven by a motor, wherein the crushable zone is further enlarged and the motional property of the vehicle is enhanced in comparison to the conventional vechicle.
To achieve the above object, according to a first aspect and feature of the present invention, there is provided an electric vehicle constructed to travel by transmitting a driving force of a motor mounted at a front portion of a vehicle body through a reduction device and a differential to front wheels, wherein the motor and the reduction device are disposed at portions of the vehicle body rearwardly of the differential, and the motor, the reduction device and the differential are disposed below a floor panel.
With the above arrangement, the motor and the reducer are disposed rearwardly of the differential and, therefore, a portion of the vehicle body laying in front of the differential can effectively function as a crushable zone upon a frontal collision of the vehicle. Moreover, since the motor, the reduction device and the differential are disposed below the floor panel, the center of gravity of the vehicle is lowered, leading to an enhanced stability with such disposition, even if the motor, the reduction device and the differential are moved rearwards of the vehicle due to a shock of collision of the vehicle, the influence applied to a vehicle compartment above the floor panel can be suppressed to a minimum. Further, the motor and the reduction device which are heavy components are disposed near the central portion of the vehicle body, leading to a mid-ship layout. This can contribute to an enhancement in the motional property of the vehicle.
According to a second aspect and feature of the present invention, in addition to the arrangement of the first feature, an inverter is mounted to a rear end of the motor for converting DC current of batteries mounted at a central portion of the vehicle body into AC current, the inverter is connected to the batteries.
With the above arrangement, since the inverter is mounted to the motor, the length of an AC power line connecting the inverter and the motor to each other is shortened. Thus, it is possible to reduce the weight, to suppress the generation of heat due to an electric resistance and to reduce the amount of noise generated. Moreover, since the inverter is mounted to the rear end of the motor, the length of a DC power line connecting the batteries mounted at the central portion of the vehicle body and the inverter to each other can be suppressed to the minimum.
According to a third aspect and feature of the present invention, in addition to the arrangement of the first feature, an inverter is provided integrally with the motor for converting DC current of batteries into AC current, and a power line for flowing of the AC current is accommodated within a casing of the reduction device.
With the above arrangement, since the inverter is provided integrally with the motor, the length of a power line connecting the inverter and the motor to each other is shortened. Thus, it is possible to reduce the weight and to suppress the generation of heat due to an electric resistance. Moreover, since the power line for the AC current, which is liable to generate noises is accommodated within the casing of the reduction device, the noise generated from the power line can be shielded by the casing of the reduction device and prevented from leaking to the outside. This is desireable for suppressing the influence of the noise on an audio device and an electronic control unit to the minimum.